Armor (Morohada-Nugi-D Gusoku) 17th century Japanese This armor is a rare example of an en suite armor of the morohada-nugi-d gusoku type (with a cuirass that simulates a bare-chested torso) from the early Edo period (17th century). Warfare in Japan changed dramatically throughout the 16th century, with the introduction of firearms and the utilization of larger contingents of troops. This necessitated significant changes in the design of armor worn on the battlefield, including the introduction of bullet resistant materials and creation of more distinctive armor forms that would aid in making individual troops more recognizable in the chaos of battle. The morohada-nugi-d gusoku is one type of so-called “modern armor” (tsei-gusoku), developed during this transitional period. Wearing a cuirass in the form of a bare-chested torso was not only a means of distinguishing oneself on the battlefield, it was also designed to intimidate the enemy.. Armor (Morohada-Nugi-D Gusoku). Japanese.